KINETIC STUDY ON CR(VI) ELECTROCHEMICAL REDUCTION IN AQUEOUS ACID SOLUTION

Hexavalent chromium Cr(VI) is a major pollutant present in industrial wastewaters common to the metal and mineral processing, as well as plating industries.This study presents results at the reduction of Cr(VI) at Pt electrode in 1 N H2SO4 deaerated solutions as a function of chromate concentration, using potentiostatic polarisation method. Tafel slope and limiting current density, the kinetic parameters, are significantly modified passing from 0.01 N to 0.1 N Cr(VI) concentration, because of the change of the equilibrium between the different chemical species, in aqueous acid solution.